The more complicated a case becomes, the more important it is to evaluate a given situation because everything is connected, one thing affecting others. This may involve reviewing paperwork, research, and some consultation as to missing details. It is like looking at the map, so you don't get lost, waste time, or fall into a trap. This is quiet time for the attorney to just think. Time well spent.
This Situation Evaluation concerns a particular part of the whole case, probably something that just happened or is coming up. It requires more than just a consultation over what your assigned attorney happens to know off the top of their head. The attorney would advise you that this needs to be done, and then a separate consultation or hotline call would be needed to go over the results.